scholarly journals Septorioza pomidora. III. Patogeniczność Septoria lycopersici Speg. oraz podatność pomidora na ten grzyb [Septoria leaf spot of tomato. III. Pathogenicity of Septoria lycopersici Speg. and susceptibility of tomato to this fungus]

2015 ◽  
Vol 30 (2) ◽  
pp. 373-384
Author(s):  
J. Marcinkowska

The resultus of this study have indicated a lack of physioloigical specialization of <i>Septoria lycopersici</i> in Poland. The susceptibility of tomato plants to this fungus depending on the age of host plant and its variety, was also studied out.

2015 ◽  
Vol 30 (2) ◽  
pp. 341-358 ◽  
Author(s):  
J. Marcinkowska

The number of <i>Septoria lycopersici</i> pycnospores necessary for inducing tomato infection was reported. In addition to this, the influence of inoculum concentration and site of tomato infection as well as the influence of air humidity and temperature on diseasee expression have been researched. Studies upon the character of <i>S. lycopersici</i> penetration and host-plant parasite interaction were made with the susceptible Bounty tomato under greenhouse conditions. The results of observations concerning the appearance and development of septoria leaf spot in the fields of central Poland were also described.


Plant Disease ◽  
1997 ◽  
Vol 81 (3) ◽  
pp. 272-276 ◽  
Author(s):  
S. K. Parker ◽  
F. W. Nutter ◽  
M. L. Gleason

Disease severity of Septoria leaf spot in rows of fresh-market tomato plants that were not staked was assessed in 1992 and 1993 following inoculation of the center plant in each row. Both temporal disease increase and spatial disease gradients were best described by the logistic model. Apparent infection rates for Septoria leaf spot epidemics averaged 0.282 day-1 (SE = 0.015, r2 = 0.96, P < 0.0001) in 1992 and 0.260 day-1 (SE = 0.011, r2 = 0.96, P < 0.0001) in 1993. Apparent infection rates remained relatively constant at increasing distances from initial foci. Estimated values for disease gradient slopes 3 to 5 weeks after inoculation ranged from -0.26 to -1.05 m-1. Velocities of disease spread ranged from 0.3 to 1.3 m/day. Results of analysis of disease severity data for these 2 years suggest that Septoria leaf spot epidemics can develop at rapid rates, but steep disease gradients limit the velocity of spread.


2015 ◽  
Vol 30 (2) ◽  
pp. 385-393
Author(s):  
J. Marcinkowska

The experiment has showed that <i>Septoria lycopersici</i> is able to overwinter as pycnospores being only in pycnidia on diseased leaves and stems of tomato. The fungus can remain alive on plant debris left on surface of soil as well as on covered plant debris. The period of pycnospores vitality in plant debris was also studied.


Plant Disease ◽  
2004 ◽  
Vol 88 (4) ◽  
pp. 397-401 ◽  
Author(s):  
I. Roloff ◽  
H. Scherm ◽  
M. W. van Iersel

Leaf spots caused by fungal pathogens or abiotic factors can be prevalent on southern blueberries after harvest during the summer and fall, yet little is known about how they affect physiological processes that determine yield potential for the following year. In this study, we measured CO2 assimilation and leaf conductance on field-grown blueberry plants affected by Septoria leaf spot (caused by Septoria albopunctata) or by edema-like abiotic leaf blotching. Net assimilation rate (NAR) on healthy leaves varied between 6.9 and 12.4 μmol m-2 s-1 across cultivars and measurement dates. Infection by S. albopunctata had a significant negative effect on photosynthesis, with NAR decreasing exponentially as disease severity increased (R2 ≥0.726, P < 0.0001). NAR was reduced by approximately one-half at 20% disease severity, and values approached zero for leaves with >50% necrotic leaf area. There was a positive, linear correlation between NAR and leaf conductance (R2 ≥ 0.622, P < 0.0001), suggesting that the disease may have reduced photosynthesis via decreased CO2 diffusion into affected leaves. Estimates of virtual lesion size associated with infection by S. albopunctata ranged from 2.8 to 3.1, indicating that the leaf area in which photosynthesis was impaired was about three times as large as the area covered by necrosis. For leaves afflicted by edema-like damage, there also was a significant negative relationship between NAR and affected leaf area, but the scatter about the regression was more pronounced than in the NAR-disease severity relationships for S. albopunctata (R2 = 0.548, P < 0.0001). No significant correlation was observed between leaf conductance and affected area on these leaves (P = 0.145), and the virtual lesion size associated with abiotic damage was significantly smaller than that caused by S. albopunctata. Adequate carbohydrate supply during the fall is critical for optimal flower bud set in blueberry; therefore, these results document the potential for marked yield losses due to biotic and abiotic leaf spots.


2012 ◽  
Vol 30 (1) ◽  
pp. 51-57 ◽  
Author(s):  
Tatiani A Modolon ◽  
Pedro Boff ◽  
Mari Inês C Boff ◽  
David José Miquelluti

Tomato crops (Solanum lycopersicum) under conventional production system are constantly treated against pest and diseases, with organic synthetic pesticides that are used may cause serious disturbance to environment and human health. This research was carried out in order to study the effect of homeopathic and high dilution preparations on pests and diseases management of tomato crop under organic production system. Two experiments were conducted under field conditions and one in greenhouse. All of them in randomized block design with the cultivar Santa Cruz Kada. The treatments consisted of homeopathic preparations Staphysagria, Arsenicum album, Sulphur, Arnica montana, high dilution preparations of Solanum lycopersicum and Solanum aculeatissimum, at the decimal (DH) or centesimal (CH) scale of hahnemanian high dilution. Bordeaux mixture, cupric preparation, and Bacillus thuringiensis were also included in weight doses. The preparation Arnica montana 12DH increased the tomato yield under field conditions. The damage incidence of small borer was efficiently reduced with applications of Sulphur 12CH that equalling to B. thuringiensis. The same treatment did not reduce the large borers. B. thuringiensis reduced also the septoria leaf spot incidence in the field. In greenhouse, the high dilution preparation of tomato at 12DH completely suppressed the septoria leaf spot and drastically reduced the same disease at 24DH. The homeopathic and high dilution preparations have the potential to be effective on replacing pesticides that are used on tomato, and could be suitable to fill legal requirement for organic production system.


2021 ◽  
Vol 5 (1) ◽  
pp. 107-113
Author(s):  
Kahlil Muchtar ◽  
Chairuman ◽  
Yudha Nurdin ◽  
Afdhal Afdhal

much needed to meet the needs of both industry and households. However, tomato plants still require serious handling in increasing the yields. Data from the Central Bureau of Statistics shows that the number of tomatoes produced is not in accordance with a large number of market demands, resulting from the decrease of tomato yields. One of the obstacles in increasing tomato production is that the crops are attacked by septoria leaf spot disease due to the fungus or the fungus Septoria Lycopersici Speg. Most farmers have limited knowledge of the early symptoms, which are not obvious, and also facing difficulty in detecting this disease earlier. The problem has been causing disadvantages such as crop failure or plant death. Based on this problem, a study will be conducted with the aim of designing a tool that can be used to detect septoria leaf spot disease based on deep learning using the Convolutional Neural Network (ConvNets or CNN) model, where an algorithm that resembles human nerves is one of the supervised learning and widely used for solving linear and non-linear problems. In addition, the researcher used the Raspberry Pi as a microcontroller and used the Intel Movidius Neural Computing Stick (NCS) which functions to speed up the computing process so that the detection process is easier because of its portable, fast and accurate nature. The average accuracy rate is 95.89% with detection accuracy between 84.22% to 100%.  


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